Narrative:The ADC aircraft was flying at FL240 en route from Port Harcourt to Lagos. At the same time a Triax aircraft had departed Lagos and was flying at FL160 towards Enugu. The Lagos controller had terminated contact with the Triax aircraft when the ADC crew requested to descend. The permission to descend was delayed to allow an ELF Petroleum bizjet to pass beneath the 727 at FL210.
When the controller finally cleared the ADC flight to descent, he thought he had cleared to aircraft to FL100 at an earlier stage, but the aircraft was still flying at FL240. When the ADC aircraft descended through FL160, the TCAS alarm sounded. To avoid a head-on collision the flight crew immediately took evasive action. During this maneuver, the Boeing rolled to an excessive bank angle and control was lost. Within 16 seconds speed had increased from 280 knots to almost the speed of sound. The aircraft crashed and disintegrated on impact.
Probable Cause:IMMEDIATE CAUSE: "The untidy traffic separation by the radar controller which resulted from the vectoring of ADK 086 towards the track of the opposite traffic TIX 185."
REMOTE CAUSE: "The error of judgement by the pilot of ADK 096 to continue his turn to heading 330 M to avoid TIX 185 and his subsequent collision avoidance manoeuver constituted the remote causes of this accident."
Loss of control
» Aviation Week & Space Technology 31.3.97 (41)
» Flight International 13-19.11.96 (6)
» The Federal Ministry of Aviation Nigeria.
|29 APR 1969
|07 JUN 1995
This map shows the airport of departure and the intended destination of the flight. The line between the airports does not
display the exact flight path.
Distance from Port Harcourt Airport to Lagos-Murtala Muhammed International Airport as the crow flies is 435 km (272 miles).